Classification
551 - Geology, hydrology & meteorology
142
550 - Earth sciences
38
549 - Mineralogy
35
624 - Civil engineering
34
553 - Economic geology
26
910 - Geography & travel
15
560 - Paleontology; paleozoology
12
621 - Applied physics
11
363 - Other social problems & services
10
300 - Social sciences
9
333 - Economics of land & energy
9
530 - Physics
9
500 - Natural sciences & mathematics
8
577 - Ecology
8
620 - Engineering & allied operations
8
001 - Knowledge
7
520 - Astronomy & allied sciences
6
631 - Techniques, equipment & materials
6
519 - Probabilities & applied mathematics
5
526 - Mathematical geography
5
576 - Genetics & evolution
5
050 - General serial publications
4
523 - Specific celestial bodies & phenomena
4
540 - Chemistry & allied sciences
4
622 - Mining & related operations
4
006 - Special computer methods
3
330 - Economics
3
414 - Phonology & phonetics
3
541 - Physical chemistry
3
900 - History & geography
3
930 - History of ancient world to ca. 499
3
301 - Sociology & anthropology
2
320 - Political science
2
509 - Historical, geographic & persons treatment
2
515 - Analysis
2
531 - Classical mechanics; solid mechanics
2
543 - Analytical chemistry
2
546 - Inorganic chemistry
2
548 - Crystallography
2
552 - Petrology
2
570 - Life sciences; biology
2
578 - Natural history of organisms
2
579 - Microorganisms, fungi & algae
2
580 - Plants (Botany)
2
610 - Medicine & health
2
662 - Explosives, fuels & related products
2
005 - Computer programming, programs & data
1
100 - Philosophy & psychology
1
140 - Specific philosophical schools
1
160 - Logic
1
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